Segregator and method of use thereof



Oct. 30, 1962 w. LAVALLE SEGREGATOR AND METHOD OF USE THEREOF 2 Sheets-Sheet 2 Filed July 18, 1960 /N VE N TOI? United States Patent Office 3,061,205 Patented Oct. 30, 1962 3,061,205 SEGREGATOR AND METHOD OF USE THEREGF Wilfrid Lavalle, Richelieu, Quebec, Canada, assignor to General Society of Refuse Recovery Limited, Montreal, Quebec, Canada Filed July 18, 1960, Ser. No. 43,372 8 Claims. (Cl. 241-24) Raw garbage consists mainly of ashes, cinders, dust,: paper, rags, glass articles, pottery, plastic, leather, and4 ferrous and non-ferrous metals, together with a major proportion of foodstuff and other'organic materials. )It has been found that` it is possibleto produce compost from the organic part of the garbage contents by removing the major part'ofthe metals, paper, rags andother` hard objects, disintegrating or comminuting the remaining portions of the garbage and digesting the 1 comminuted` material in special apparatuscalled digesters which form part of a co-pending application Serial Number 43,371, led July 18, 1960 in the name of the same inventor and entitled Digesten .i

:They general object of-.the present .invention resides in the provision of a machine incorporating breaking means for breaking'the garbage or at least fa major portion.

thereof into small particles,` screening means for screening the broken garbage and collecting the screenings as a.

separate'stream, magnetic separating means for sorting out and discharging the ferrousmaterial as a separatev stream, and conveyor means for removing the remaining unscreened coarse material; t l 1 An important object of the invention" resides in the provision of a segregator whichv provides cleaning of the paper contained in the raw garbage by thev mutual rubbing of the paper Ipieces combined with the action of dust in the segregator so as to obtain paper of saleable grade.

Another more specific object. of the present invention resides in the provision of a segregator'of improved and relatively simple and sturdy construction, having a large capacity and having new and improved driving means forV the rotary part thereof. i 1

Yet another important object of the invention ,resides in a segregator of the character described in which the magnetic separating means are of novel and improved con# struction.l .v

The foregoing and other important objects of the present invention will become more apparent during the following disclosure` and by referring to the drawings, in which: l'

FIGURE l' is a longitudinal section of the segregator in accordance with the invention, drawn on a larger transverse scale than the longitudinal scale;

lFIGURE 2 is a cross-section along line 2 2 of =FlG URE l.;

FIGURE 3 is a cross-section along line-3 3 of -l-TIG- URE l;

FIGURE 4 shows a detail of the drive for the rotary screen taken along line 4-4 of FIGURE 2; and` FIGURE 5 is a plan -view of the inside conveyor system and taken along line 5-5 of FIGURE 3.

Referring now more particularly to thedrawings -in which like reference characters indicate like elements throughout, the segregator comprises abase framework 1 constituted by welded I-beams and supporting the entire machine, the base 1 being 4mounted in an inclined position with respect to floor F. A screen assembly 2 of cylindrical shape and open at both ends, is mounted for rotatable movement on the base 1. The screen assembly comprises a heavy wire screen 3, the diameter of the wire being about 1/2 inch and woven to provide rectangular openings of about 11/2 inches wide by 6% inches long. The screen 3 is supported by and surrounds a plurality of longitudinally extending baffles or lifting blades 4 equally angularly spaced and lying in radial planes with respect to the axis of rotation of the screen assembly Z. The blades 4 are rigidly secured to the main leg of ring members 5 of T-shaped cross section, the transverse -leg 6 of which provides a running surface for the supporting wheels 7 and driving wheels `8, shown in FIGURES 2 and 4, and which are rotatably mounted at the outer end of uprights 9 secured to base 1 and reinforced by braces 10. The wheels '7 and S are associated with each ring member 5 and on eachside of the segregator; more specifically, on one side of the segregator there is a pair of supporting metal wheels 7 in metal to metal contact with each ring member 5; on the other side of the segregator, there is a group of one supporting wheel 7 and one driving wheel 8 associated with each ring member. The driving wheels 8, eachhas a pneumatic tire in frictional contact with the running surface of the ring member 5; the diameter of wheel 8 and the air pressure of its tire are selected such that the major portion of the'weight of the screen assembly is supported by the metal wheels 7, while there is a sufficient friction for rotating the .screen assembly through the driving wheels 8, one for each ring member'S. A longitudinally extending shaft `11 is connected to the two groups of wheels 7 and Son one side of the segregator and is driven through a speed reducing unit and electric motor 12. The speed of rotation of the screen assembly 2 is very slow being of the order of about four revolutions per minute.

A diametrically extendingY brace 113 is secured to the ring member 5 nearer the inlet end 14 of the segregator and supports at the center thereof, a bearing 15 for one end of an axially extending shaft 16, the other end of `which projects outwardly from the inlet opening 14 and is supported in bearing 17 mounted on support 18 outside of the screen assembly. An electric motor 19 mounted on support 1S drives the shaft 16 at a suitable speed through the belt and pulley assembly '20.

A plurality of radially extending 'breaker arms 21 are rigidly secured to shaft 16. Preferably, the breaker arms 21 are mounted in rows making a 90 angle between -one another and their outer ends are inclined at about 4 to prevent clogging and to move the material towards the discharge end of the segregator. The breaker arms are `close together and near the brace 13 so as to leave sutiicient space between said arms and the feeding hopper 22 supported by braces 23 such that the raw garbage fed by the hopper -will drop onto the screen 3. The garbage discharged within the screen assembly 2 will, during rotation of said screen assembly, be lifted by the lifting blades 4 and progress slowly throughout the screen assembly 2 towards the discharge end of the segregator while the fine particles will pass through the screen 3 and fall `onto conveyor 24 extending underneath thescreen assembly 2 along the entire length of the segregator. The garbage fed at the inlet end of the segregator will eventually fall on top of the breaker arms 21 whereby the material will be disintegrated or 'comininuted except substances, such as rags, paper,

bones, and metal, and other hard objects which will remain as coarse particles and will progress towards the outlet end of the screen assembly. The screening is collected by conveyor 24 and is moved towards the outlet end of the segregator until it falls onto an elevating conveyor 25 to be conveyed to the digesters, as explained in co-pending patent application Serial Number 43,425, entitled Method and Apparatus for Treating Garbage.

As a great deal of dust is produced Within the segregator, the screen assembly is enclosed by an outer stationary shell 26 of generally cylindrical shape open at its ends and having inclined and converging lower portions 27 for directing the screened material onto the central conveyor 24, as shown in FIGURE 2. The ends of shell 26 are preferably closed by means such as ilexible curtains 53 and one or more exhausters communicate with the interior of the shell 26 through duct 54 to suck the dust which is returned to conveyor 24, as dust constitutes an excellent ingredient for making compost.

The inside of the shell 26 is lined with longitudinally extending pipes 28 arranged in a continuous coil and having an inlet 29 and outlet 30, `as shown in FIGURE 2, to thereby circulate steam within the shell 26 and warm the garbage material, in order to dry the paper in the garbage and initiate the biochemical reactions to be completed in the digesters.

At the outlet end portion of the segregator, the material within the same is subjected to a magnetic separating step which is obtained by a magnetic separator consisting of a permanent magnet plate 32 supported by a bracket 31 disposed on the outside of the shell 26, said magnetizing plate 32 being a permanent magnet, disposed as close as possible to the outer surface of the screen assembly 2 and having a longitudinal curvature corresponding to the curvature of the screen assembly 2 and being coaxial with the axis of rotation of the screen assembly. Magnetizing plate 32 is supported by non-magnetic bolts 33 to bracket 31. Opposite plate 32, the screen 3 is interrupted and replaced by a cylindrical plate 34 of non-rnagnetic material. Similarly, the lifting blades 4 are interrupted in the magnetizing area and replaced by portions 35 of non-magnetic material. The lmagnetizing plate 32 extends nearly through half a circle, its top end 36 lying in a vertical plane passing through the axis of rotation of the screen assembly 2.

A pair of conveyors 37 and 38 extend side by side, horizontally through the center of the outlet end portion of the screen assembly 2, and protrude outwardly of the segregator. The conveyors 37 and 38 are supported by `and are mounted on each side of `a central horizontally extending bar 39 which is supported in cantilevered fashion on top of uprights 40 outside of the outlet end of the screen assembly 2. The longer conveyor 37 terminates at its inner end just short of the magnetizing plate 32, as shown in FIGURE l, at 41, and extends a substantial distance outside of the segregator to terminate at 42. Conveyor 37 is disposed in the sector zone of the segregator embraced by magnetizing plate 32, as shown in FIGURE 3, and its supporting frame is provided with a lateral deflector plate 43 extending along the inner portion of said conveyor 37. The bar 39 extends in a plane passing through the longitudinal axis of the screen assembly 2, and the conveyor 38 is supported by said bar in the half portion of the screen assembly outside of the sector zone embraced by magnetizing plate 32. Conveyor 38 has its inner end 44 terminating a little past the upstream side of the magnetizing plate 32 while its outer end 45 is outside the segregator but is upstream of the outer end 42 0f conveyor 37. A deector 46 is disposed along the outer side of the portion 38' of the conveyor 38 in register with the magnetizing plate 32. Finally, an inverted V- shaped deector plate 47 extends upwardly from bar 39 in the magnetizing zone. The portion 38 of the conveyor 38 downstream from portion 33 is covered by an inverted V-shaped hood 48.

As the coarse material within the screen assembly 2 progresses towards the outlet end of said assembly due to the inclination of the latter, the ferromagnetic components in said coarse material will adhere to the cylindrical portion 34 of the screen assembly when reaching the area of magnetization produced by plate 32, upon lifting of the material by the lifting blades 4, all nonferrous material will automatically fall back into the bottom of the screen assembly, because conveyor 37 terminates downstream from the magnetized zone. The ferromagnetic metal which adheres to the cylinder p0rtion 34 will continue so until it reaches a point opposite the upper end 36 of the magnetizing plate 32. At this point, the ferrous material will become demagnetized and will drop onto the conveyor 38 and be conveyed out of the segregator by said conveyor 33; at the outer end 45 of conveyor 38 the ferrous material will drop onto another transversely directed conveyor 45 for directing the ferrous metal to a further treating station described in Athe above noted co-pending application Serial Number 43,425 entitled Method and Apparatus for Treating Garbage.

As the materials withinrthe segregator have to be lifted through at least four or five turns of the screen assembly before progressing through the magnetized zone, all the ferrous metal would then be separated from the remaining portion of the coarse material and be conveyed out of the segregator by conveyor 38. Ferrous metal which does not adhere well to the peripheral portion 34 in the magnetized zone, due for instance to the interposition of paper, will fall 4back into the bottom of the segregator before reaching the top point of the segregator. However, ythe yferrous metal will not be conveyed by conveyor 37 due to the 'fact that the latter terminates short of the 4magnetizing area.

Once the ferrous metal has been separated, the remaining portion of the material still in the segregator will progrissively move out of the magnetizing zone and be lifted again by the lifting blades 4 so that all of said portion will eventually fall tonto conveyor 37 and be discharged out of the segregator. IIn the zone of the segregator downstream from the magnetizing zone any material lifted by 'blades 4 and non falling in conveyor 37 will fall on top of hood 48 protecting conveyor 38, and then back onto the bottom of the segregator.

The conveyors 37, 38, 24 and 25 are preferably all driven yfrom la common motor drive through chain and sprocket arrangement 49.

The portion of conveyor 37 protruding from the segregator proper is `accessible to manual operators who will manually sor-t out non-ferromagnetic metal pieces, hard bones, rags, leather, and the like, while leaving paper on the conveyor, which will carry said paper to a baling press. The bones, leather, and the like are directed to a grinder and the ground material is redirected to the lifting conveyor 25 to go to the digesters.

As noted above, the entire screen assembly 2 is entirely supported by wheels 7 and 8. Due to the inclination of the screen assembly, it is only necessary to provide a thrust wheel 50 rotatably supported by the upright 40 nearer the segregator to prevent longitudinal displacement of the screen assembly.

In order to prevent damage to the outer shell 26 and steam pipes 28 by material thrown under centrifugal' force by breaker arms 21, a curved plate 51 lines the inside of the shell and passes radially inwardly of the pipes in the 4area of the breaker arms, as shown in FIG- URE 1. The drum rotates anticlockwise as shown by arrows 52 in FIGURES 2 and 3.

As noted above, a great deal of dust oats in the segregator enclosure. This dust, which is dry, acts as an absorbent to aid in the cleaning of the paper pieces which `are lifted by blades 4 and rub against one another with the interposition of said dust. Thus the soiled paper in the raw garbage is cleaned to considerable extent and the outgoing paper is of sufficient cleanliness to be sold as a 4mixed paper.

The dust itself is exhausted from the segregator and returned to the conveyor 24 to constitute an important ingredient for making compost.

While a preferred embodiment in accordance with the present invention has been illustrated and described, it is understood that various modifications may be resorted to without departing from the spirit and scope of the appended claims.

What I claim is:

1. A segregator comprising a cylindrical screen having inlet and outlet ends, and downwardly inclined towards said outlet end, means for supporting and rotating said cylindrical screen about its longitudinal axis, lifting |blades extending longitudinally of the screen and radially inwardly projecting from the latter, longitudinally extending means under said screen for receiving screened material, a rotatable shaft ex-tending within the upstream portion of said screen, breaker arms secured to said shaft within said screen, means to drive said shaft, and magnetic separating means in the downstream portion of said screen, -said magnetic separating means including a stationary curved magnetized plate concentric with the axis of rotation of said screen, extending in close proximity with a limited longitudinal area of said screen on the outside thereof, and extending through less than 180 of said screen terminating near the top thereof, a stationary frame entering within the screen through the outlet end thereof and a conveyor supported by said frame extending within the said screen to a point in substanti-al alignment with the upstream edge of said magnetized plate, said conveyor being substantially horizontally disposed in a vertical half section of the cylindrical screen outside of the sec-tor zone defined by said curved magnetized plate, whereby non-magnetic material component lifted by said lifting blades during rotation of said screen will fall short of said last named conveyor in said magnetized zone, and magnetic material will be further lifted upwardly and adhere to the screen due to magnetization by said magnetised plate until it moves beyond the top end of said plate, whereby it will drop onto said conveyor.

2. A segregator as claimed in claim 1, including spaced transverse ring members secured to and supporting said cylindrical screen and lifting blades, said ring members providing an outer cylindrical running surface, said means for Vsupporting and rotating said screen including a supporting and a driving wheel secured to a common shaft and in engagement with the same running surface of a ring member, said supporting wheel being made of metal in direct contact with said surface for supporting the major portion of the weight of Asaid cylindrical screen, said driving wheel being a pneumatic tire wheel in frictional engagement with said same running surface, and means to rotate said shaft.

3. A segregator as claimed in claim 1, wherein said breaker arms extend radially outwardly lfrom their supporting shaft, and are arranged in aligned rows around said shaft.

4. A segregator as claimed in claim 2, wherein said ring members have a T-shaped cross section with their transverse leg extending outwardly of said screen and providing said running surface and their main leg inwardly directed and serving as support for said lifting blades which are rigidly secured thereto.

5. A segregator as claimed in claim 1, wherein said means to drive the shaft provided with the breaker arms, rotate the said last named shaft at a much greater speed than the speed of rotation of said cylindrical screen.

6. A segregator as claimed in claim 1, further including an outer stationary shell, enclosing said screen and heating pipes lining the inside of said shell.

7. A segregator as claimed in claim 1, further including a second conveyor extending side by side with said first conveyor, downstream of the magnetizing area, and disposed in the sector zone of said magnetizing area to receive non-magnetic material lifted by said lifting blades, and discharge from lthe segregator the material remaining therein.

8. A method of segregating raw garbage containing foodstuff, metal pieces, paper, rags, dust and other materials as normally found in garbage, comprising the steps of `feeding raw garbage to a closed space, subjecting said garbage to a breaking ac-tion, screening the comminuted material, discharging the screen material as -a rst separate stream, confining in said closed space dust produced by the breaking step, agitating the unscreened material containing a major portion of paper so as to rub the paper pieces against one another with the interposition of dust in said closed space in order to clean the paper, magnetically separating the unscreened ferromagnetic material, discharging the latter as a second separate stream and discharging the remaining unscreened material as a third separate stream which contains said cleaned paper.

References Cited in the file of this patent UNITED STATES PATENTS 87,716 Smith Mar. 9, 1869 470,456 Thompson et al M-ar. 8, 1892 1,034,969 Brown Aug. 6, 1912 1,784,983 Borton Dec. 16, 1930 1,837,782 Little Dec. 22, 1931 2,721,035 Lankford Oct. 18, 1955 FOREIGN PATENTS 436,138 Great Bri-tain Sept. 26, 1935 

